Moving a plumbing stack out of a bearing wall in Centretown?

Moving a plumbing stack is plumbing work, and that part is outside the scope of what this site covers. What falls within scope here is the carpentry side: the framing that gets cut, patched or rebuilt when the stack moves through a bearing wall.

When a plumber relocates a stack inside a bearing wall, studs and plates are often cut or notched to make room. The carpentry question is whether what remains meets the framing rules and carries the load safely. The 2024 Ontario Building Code sets limits on how much a load-bearing stud can be reduced: it must keep at least two thirds of its depth after notching or drilling, unless the member is reinforced. Top plates must keep at least 50 mm. If a hole is drilled rather than notched, it cannot be more than one quarter of the member's depth and must sit at least 50 mm from the edges. For engineered joists or beams, we found no general limit in this part of the Code, so ask the designer before anything is cut.

Beyond the framing rules, the load path matters. In a bearing wall, every stud that is cut or removed needs the load redirected somewhere. A carpenter or designer looks at what is carrying the floor or roof above, decides whether a temporary header or doubled framing is needed around the opening, and confirms the load reaches the foundation. That is not something to sort out after the plumber has already opened the wall.

The carpentry scope on a job like this covers: assessing what the wall carries before anything is cut, any temporary support while the wall is open, reframing around the new stack location, and patching back to a finished surface. Because this involves structural framing in a bearing wall, the City of Ottawa lists structural alterations as permit work; confirm with Building Code Services before the wall is opened, and ask who on the team is applying.

Before work starts, have the written contract with the full scope and price, any permit in hand, and any design drawings that show how the framing is being rebuilt around the new stack location.